1. Field of the Invention
The present invention relates in general to a computer apparatus, power supply control method and program, and more particularly, to a computer apparatus, method and program having a wake-up function.
2. Description of Related Art
There has been an increasing demand, particularly from an environmentally-oriented viewpoint, to provide for the capability to reduce powering needs with respect to the powering on and powering off of computer-related devices, and more particularly, there is appears to be an increase in the interest of using stand-by power requirements, such as where the power is supplied from a power supply apparatus (such as an AC adapter for instance). According to the powering criteria set forth by Eco Mark™ (trademark of Japan Environment Association) since 2000, the powering on powering off is 1 W or less for a typical computer-related model including the AC adapter with no wake-up function, and 3 W or less for a typical computer-related model with a wake-up function.
As used herein, the term “wake-up function” is a function of starting up a distant computer by turning on the power thereof by remote operation, thereby powering on the computer by an instruction from a network based on an operation at a remote location instead of being turned on manually by an operator locally. WAKE-ON-LAN is a representative instruction set thereof, and such a function allows powered-off computers to be collectively managed at the center.
On the other hand, although power saving strategies for computer apparatuses have been of interest in recent years, emphasis has been placed primarily on power saving options related to battery operation and battery capacity holding time thus far. As a result, the focus has been primarily related to developments that are directly related to functions and apparatuses having AC power supplied from an AC adapter, such that the savings has not necessarily been pursued in terms of the electric power.
For the present invention, the system includes active logic which consumes power during the instantiation of a wake-up even if the power is off. As a result thereof, the models for realizing the wake-up function has the power on the power off increased compared to the cases of having no wake-up function as seen in the criteria of the Eco Mark. More specifically, as for a factor of power consumption on the wake-up, it can be pointed out that a power source for wake-up VAUX of a subject Ethernet adapter is turned on in the case of WAKE-ON-LAN in order to start up a PC by recognizing a specific packet from a network.
FIG. 5 is a diagram for explaining current control of standby power source. The current control has an OS (Operating System) 201 which is basic software, a PM BIOS (Basic Input/Output System) 202, a core chip 204, a system ASIC 207 which is an integrated circuit, and a switch 210 turning on and off a main source VCCM and an auxiliary source VCCAUX1. In addition, it is arranged so that a plurality of devices 211 (DEV1 to DEVn) are connectable as the devices to which the main source VCCM and auxiliary source VCCAUX1 are supplied. The core chip 204 has a CMOS 206 which is a memory changeable by a setup program of a power management control register 205 and PM BIOS 202 for managing a power supply state of a computer system. In addition, the system ASIC 207 has a gate array 208 for performing switch control. The system in FIG. 5 can perform control so as to have the switch 210 switched by the gate array 208 and supply the auxiliary source VCCAUX1 as the standby power to the devices 211.
Here, as shown in FIG. 5, the system configuration related to the current power supply adopts a common power source design for the purpose of simplifying the design even in the case where there are a plurality of devices 211. For that reason, even in the case where it is configured to have the auxiliary source VCCAUX1 supplied for the sake of power consumption, 30 the auxiliary source VCCAUX1 is simultaneously supplied to all the devices 211 by switching the switch 210. As a result thereof, it requires unnecessary standby power requirement for the devices having no wake-up function so that the overall standby power requirement increases and so a sufficient power saving effect is not obtained.
In addition, power control during battery operation is currently performed by the system. However, the power for wake-up on the power off is not controlled in a state of being connected to the AC power in particular. As a result thereof, the standby power is supplied to the system regardless of whether or not a device being able to realize the wake-up function is included and whether or not the wake-up function is set up, and so wasteful power has been consumed.
The present invention has been achieved in order to solve the above technical problems, and an object thereof is to reduce the standby power requirement in the computer apparatus supporting the wake-up function.